Smoothing apparatus



1945. D. A. WALLACE 2,393,207

SMOO THING APPARATUS I I Filed Feb. 4, 1944' 3 Sheets-Sheet II Inn-mining 6/ III" 5 INVENTOR.

.Uafzk/ 1?. Wallace. I

Jan. 15, 1946. D. A. WALLACE 3,393,207

SMOOTHING APPARATUS I Filed Feb. 4, 1944 I s Sheets-Sheet 2 IN VEN TOR.

B 41 12? flill allece.

Patented Jan. 15, 1946 SMOOTHING APPARATUS David A. Wallace, Detroit, Mich., assignor to Chrysler Corporation, Highland Park, Mich., a corporation of Delaware Application February 4, 1944, Serial No. 521,061

3 Claims.

This application relates to a smoothing apparatus. More specifically it relates to an apparatus for polishing a concave surface such as that of a reflector.

sponding rotative and revolving movements of the abrading element through contact of the latter with the work.

Other objects will appear from the disclosure.

An object of the present invention is to pro- In the drawings, vide an improved smoothing apparatus involv- Fig. 1 is a front view of the novel apparatus ing a rotating work holder and rotating smoothof the present invention; ing means. Fig. 2 is a side view of the same apparatus;

Another object is the provision of improve-' Fig. 3 is an enlarged vertical sectional view ments in an apparatus for smoothing a concave taken through the apparatus, and surface of an article. Fig. 4 isa sectional view taken on the line 4--4 A further object is to improve an apparatus of Fig. 3. I for providing a polished concave surface on an The reference character l0 designate a l article, involving a driven article holder, driven porting framework, upon the top of which is polishing elements, and control of the relative mounted by means of bearings H and I2, a rockspeeds of the holder and polishing elements and able member I3. The rockable member I3 carshifting of the polishing elements across the ries integral bracket portions 14 to which is afholder. fixed a stand I5 for an electric motor l6. One

One of the main objects of the invention is the end of the rockable member 13 carries a clampprovision in apparatus of this kind of mechanism ing part I1 integral therewith to which is pivfor producing relative movement between a con- Otally Co e t a mating C p Part The cave work surface and a freely rotatable abradclampingparts are held together by a swing bolt ing element which is the resultant of rotative I9 and a wing nut 20 threaded thereon. Clampmovement of the work and revolving of the ins part8 and hold a bearing 2! n Which is abrading element about angularly related axes mo d Sleeve The lengthwise position of and of an additional component movement of the the bearing 2| upon the sleeve 22 is fixed by set abrading element about its rotative axis resultcollars 23. The S eeve 22 s a lower enlarged ing from the action of the first two mentioned end 24 in Which are threaded ee P s A component movements while the abrading elerod 26 is slidably and rotatably mounted within 'ment and work are engaged together. so the sleeve 22 and has adjacent its upper end a An additional object of the invention is to proshoulder 21 against which rest weights 28. The vide apparatus of this kind which is adapted to w i hts 8 hav tr openings th u ch urge the abrading elements against the work surthe p t o the d 6 beyond the shoulder 2! face with uniform and relatively light pressure exbends- The rod 25 has a Sp er a wer end of such value as to accommodate angular adjust- 29 retained in a block 39 bymeans Of a perforated 'ment of the abrading elements with respect to Plate 3| attached to the block 39 y Screws portions of the work of diverse curvatures with-- The block 3!] is the central PO t f a a eout scratching or otherwise injuring th k work 33 which also includes three outwardly exsurface. tending arms 34. Upon each arm 34 is adjust- Other objects of the invention are to provide y mounted a mem r 35 Which y be fixed freely rotatable and angularly variable abrading t0 the m 34 y means of a Set screw 38. Each elements in apparatus of this character which member 35 has a lower pointed end fitt i t-0 are-adapted to become self-adjusted to portions a recess 38 n a c i 39 orm p Of a of a eon av d urf e f Varying curvatures t polishing element All. Polishing element 4%! also provide means for drivjngly producing a relative includes a plurality of segments 4! formed of revolving movement between a work surface and Polishing material and arranged a r yfreely rotatable abrading elements which, when There are three polishing elements one assothe work and elements are engaged, causes a siciated with each arm 34. A pu 42 is re multaneous rotative movement of the latter; to to the upper end of the sleeve 22 y a Set Screw provide means for drivingly rotating the work 43. The pulley 42 is connected with a pulley 44 in a selected direction with respect to abrading by a belt 45. The pulley 44 is carried and driven elements during rotation and revolution thereof by the motor l6, which also supports a housing in the foregoing manner, and to provide appa- 46 having gearing, not shown, therein for drivi'atus of this kind in which the rotation of the ingly connecting the pulley and the shaft of the work alone can be relied upon to produce corremotor.

Positioned within the lower part of the framework I is an electric motor 41 which carries at one end a housing 48 for gearing, not shown, which connects the motor 41 with a pulley 49. The pulley 49 is connected by a belt 50 with a pulley i secured to a vertical shaft 52. The lower end of the shaft 52 is supported by a bearing 53. The upper part of the vertical shaft 52 carries a; title; Holder; 54 upbawiiiehgr'ise si tloned an article such as a reflector-55 having a concave inner surface 56 to be polished, which may be of parabolic form. The reflector 55 1s retained in the holder 54 by means of; cleats- 51,

extending slightly inwardly from the upper edges of the holder 54.

:by bolts 63 to a block 64 mounted upon an interm ia erer @i h ame ork 1:

As, s vid n min 3 the l e e t e the rod 26 are slightly inclined to the vertical, and his i l n on s e em i l ane'm ihi in by means of an arm 65 s'ecuredto the roclgable m m e t ed W1 5.- i eid a i in a bracket 68 secured to, the uppe part of the framework iii, and a nut (iflbonnelct d to the armbfij and having (threaded enga ement with the threaded roll 66; Fingers Ill projecting from the nut 63 facilitate. adjustment of the nut along the threaded rod 66 an'din this way the" rock'- ab member '3 s oc ed and the angle .o t sleeve, 22 and therod 26 tothe, vertical is adju te a n eration the. ol in m nt 4. are in n a ment w h. t e oncave strap 545 f h fle o 5.5, hbwn. n la 3.- he reflec o 5 is rotated by the motor 4! acting through the pulists 6. nd L af 3, and the ho d The poli hing e emen efl a o v d ahqutthfe x s jof thesle'eve Z2 and each element is rotated about an axis extending ng th i -7 d I this is llg w thin h oli his leme ts a d ein ncl ned to e ax of ota at h heldelf 54 and t e refle 5.5- The d ct f ro ation Qf thepolishin's eleme s 4? 'qp i t9 the direction of rotation of the reflectorio and the speed of rotation of the polishing elements 45 is pr ab y le a th t Of h fri flebtor 55 and indivisible in it. With thesleeve 2; at a angle to th e a as how i F et pol sh ng em nts i car a PQ fiQ l th eflec 5 rom a a e t t e cen her e to n a th u er g Since the di c on o tat n ar were .01 nothe h r lat ve, speed he re sh el m t wi h reseet t e re c or wi b high a he ter edge o i ei' fir ei f the reli hi sm ei m v n in e rect n at thi res n an he ref qr in the osit i testio d e a ve speed at the po is in e ernent with respect to the refleotor will be low at a re on. ear t e r I the reflector, th ihing elemen s an th s r'mov n in th same direction at this region. The polishing action is, of course, greater with greater relative speed between reflector and polishing element. "Th a a emen is of a vantage, $0 by virtue 1 119; @Q in? 'e l l" p lli i Q Smoothing actiqn takes place near the outer edge where a given are a is passed over by a polishing element a relely small number of times, and the lesser poli's hmg' action will talge place adj acent the] center w ere a iven area ispassed over by a DQhShln element a relatively great number of times. The

The holder 4ycarries at its under side a thrust collar i'aa s'ecured thereto'by bolts 59. The thrust collar 58 has a projectingspeed of the reflector 55 may be 60 R. P. M. for example, and the speed of the polishing elements 4| may be 18 R. P. M. It is to be seen that 18 is not divisible into 60 and therefore, the polishing elements will not immediately pass over the same regions of the reflector 55 in such a way as to form grooves at the parts passed over. Appropriate pressure of the polishing elements 40 aga'ilis't "-tl iereflector 55 is'appliedfthrough the weights 28 acting against-the upper "end of the rod 26. The pointed end 31 on the member 35 carried on the arms 34 and the recesses 38 and the polishing elements 40 allow the appropriate tilting or 'the polishing elements in conformance elements. The polishing elements 40 are driven byflhemotor l6 aoting through the pulleys 44 and 2 the sleeve 22, and the pins 25, the latter engaging the arms 34. The connection of the framework 33 to the rod 26 in the spherical end 25 9 t e ed is: n e bloc O'f' amewor 33- provides a universal joint basses these parts so that the framework as are; a priately. Three polishing elements 411. 'arefpiovided, for this number assures "a proper contact with the surface t be polished. The 'spacing'ijf one member 35 from the rod 26 may manta thespacing or the other two members 35 inor'd'r uniformly to apply the polishing action to. the entire surface of the work; so that thefone ishing element 411. does not overlap the othertwo or overlap them to a desired ektent. "Irre pe ing of each may be diiferent if desired. Ifthe complete area of the concave. surface 55 is not covered by one position of theslkeve 22;, sleeve may beadjusted with respect to the, vertical to assure the covering of theoompletearea. As has been stated, the reflector 55 isrotated about its own center. and the polishing elements are revolved, i. e., move, about an axis spaced m em a d oi cide t with t e x of atetion of the driving sleeve 22; Consequently; the polishing elements rotate about their own axes passing through the pointed ends 31 and the. recesses 3,8. This 'rotatio'nrmay' vary as the element passes across the surface 56f T I The absolute and relative speeds of the article s i e p li he an f the o hi gemeri may be varied to suit the'a'rticle and the type or polish: ing or smoothing desired. The terms f-polishing" or smoothing have been used throughout the specification, and it is to be understood that they are to cover an action of relative movement between tool and work that may involve either rough or smooth removal of materialorjthe press;- ing down of the surface of the work.

In an alternative mode of operation only the work is rotated, and there is no positive revolvij 'g of the, polishing elements, the drag of the. work upon the polishing elements causing them to revolve about the sleeve 22. and to rotate. about their own axes. V

In a further alternative mode of operation the polishing elements may be revolved ppsitively in thesame direction as the work. Although'this mode'may'not equalize total polishing action at the center and the, edges of 'the work 'as will the first described mode of operation, there may be conditions under which this equalizing is not mandatory or other conditions under which an increased polishing action at the edges desirable. I w l e p a e fr m l iQP l d i' the ha a e ar 'nlevel missea rerae has been provided which operates by smoothing of the surface to be polished. The apparatus has been illustrated as applied to the polishing of a concave surface. The principles of the apparatus may be applied also to convex and plane surfaces without a departure from the spirit of the invention.

The intention is to limit the invention only within the scope of the appended claims.

I claim:

An apparatus for smoothing a curved surface on an article, comprising means for rotating the article, a plurality of spaced smoothing elements, and means for rotating the smoothing elements about an axis spaced from the axis of rotation of the article and between the smoothing elements, said last mentioned means including a driving sleeve, a rod mounted in the sleeve for rotation and axial movement with respect thereto, a framework engaging the smoothing elements to maintain them in spaced relation and to permit tilting of the smoothingelements in conformance with the curvature of the surface being smoothed, means connecting the framework to the rod in a universal joint for applying pressure from the rod to the smoothing elements independently of the sleeve, and driving means on the sleeve engaging the framework to cause the driven sleeve to drive the framework.

2. An apparatus for smoothing a concave surface on an article, comprising means for rotating the article, a plurality of spaced smoothing elements, and means for rotating the smoothing elements about an axis spaced from the axis of rotation of the article and between the smoothing elements in a direction opposite to the direction of rotation of the article, said last mentioned means comprising a framework having portions projectinginto recesses in the smoothing elements for rotating them and permitting them tilting movement while maintaining them in engagement with the surface being smoothed, a driven sleeve having driving engagement with the framework, a rod mounted in the sleeve for rotation and axial movement with respect thereto, means connecting the one end of the rod and the framework in a universal joint, and a weight carried on the other end of the rod for acting through the rod and the framework to apply pressure to the smoothing elements.

3. An apparatus for smoothing a concave surface on an article comprising means for rotating the article, three spaced smoothing elements, means for rotating the elements in contact with the surface being smoothed about an axis between them and spaced from the axis of rotation of the curved surface in a direction opposite to the direction of rotation of the article, said last mentioned means comprising a framework formed of three arms extending outwardly from a common central region and guiding and maintaining the smoothing elements in contact with the surface being polished, a driven sleeve, three parts projecting from the driven sleeve into engagement with the three arms for rotatin the framework, a rod mounted in the sleeve for rotation and axial movement with respect 'to the sleeve, and means forming a universal connection between one end of the rod and a central region of juncture of the arms of the framework, and means acting directly on the rod and independently of the sleeve to apply pressure to the smoothing elements.

DAVID A. WALLACE. 

